Medication overuse headache

Medication overuse headache (MOH) is a chronic secondary headache condition attributable to overuse of acute medication(s) by an individual with a pre-existing primary headache disorder (almost always migraine or tension-type headache). Patients with MOH suffer from a headache on more days than not.

MOH is a clinical diagnosis based on careful history-taking and use of a headache diary, together with a normal neurological examination. No investigations are required unless there are red flag symptoms or signs that suggest the need to exclude an alternative, more serious cause for the headache.

Education and advice is the first step in managing MOH and may be sufficient on its own to resolve the condition. Withdrawal from the acute medication may be abrupt or tapered, depending on the class of medication that is overused. Symptomatic treatment for withdrawal symptoms may be needed.

Initiation of a preventative regimen that targets the underlying headache disorder is typically used to facilitate withdrawal from the overused medication. For patients with underlying migraine, the recommended options are topiramate, botulinum toxin type A, or calcitonin gene-related peptide (CGRP) antagonists. For those with underlying tension-type headache, amitriptyline is most commonly used.

Inpatient treatment may be necessary for patients who are withdrawing from opioids, barbiturates, or benzodiazepines.

Medication overuse headache (MOH), also known as rebound headache, is defined as a secondary headache occurring on ≥15 days per month in a patient with a pre-existing primary headache disorder who has been overusing acute/symptomatic headache medication. Overuse is defined by use of the acute medication(s) on ≥10 or ≥15 days/month (depending on the medication class) for more than 3 months.[1]International Headache Society. 2018 International Headache Society international classification of headache disorders (ICHD), 3rd edition.​ 2018 [internet publication]. https://ichd-3.org Most individuals affected by MOH have a history of episodic migraine and/or tension-type headache (TTH) as the underlying primary headache disorder.[2]Schwedt TJ, Alam A, Reed ML, et al. Factors associated with acute medication overuse in people with migraine: results from the 2017 migraine in America symptoms and treatment (MAST) study. J Headache Pain. 2018 May 24;19(1):38. https://thejournalofheadacheandpain.biomedcentral.com/articles/10.1186/s10194-018-0865-z http://www.ncbi.nlm.nih.gov/pubmed/29797100?tool=bestpractice.com [3]Bigal ME, Serrano D, Buse D, et al. Acute migraine medications and evolution from episodic to chronic migraine: a longitudinal population-based study. Headache. 2008 Sep;48(8):1157-68. https://headachejournal.onlinelibrary.wiley.com/doi/10.1111/j.1526-4610.2008.01217.x http://www.ncbi.nlm.nih.gov/pubmed/18808500?tool=bestpractice.com [4]Hagen K, Linde M, Steiner TJ, et al. Risk factors for medication-overuse headache: an 11-year follow-up study. The Nord-Trøndelag Health Studies. Pain. 2012 Jan;153(1):56-61. http://www.ncbi.nlm.nih.gov/pubmed/22018971?tool=bestpractice.com ​​​​​​ The typical history is for the primary headaches to increase in frequency, accompanied by escalated intake of acute headache medications, leading to a transition from an episodic to chronic headache.[5]Wakerley BR. Medication-overuse headache. Pract Neurol. 2019 Oct;19(5):399-403. http://www.ncbi.nlm.nih.gov/pubmed/31273078?tool=bestpractice.com [6]Diener HC, Kropp P, Dresler T, et al. Management of medication overuse (MO) and medication overuse headache (MOH) S1 guideline. Neurol Res Pract. 2022 Aug 29;4(1):37. https://neurolrespract.biomedcentral.com/articles/10.1186/s42466-022-00200-0 http://www.ncbi.nlm.nih.gov/pubmed/36031642?tool=bestpractice.com ​​​ This topic covers MOH where the patient has a background of migraine or TTH as their primary headache disorder.​